Contralateral psoas hematoma after minimally invasive, lateral retroperitoneal transpsoas lumbar interbody fusion: a multicenter review of 3950 lumbar levels

Effect of Unintended Tissue Injury on the Development of Thigh Symptoms After Lateral Lumbar Interbody Fusion in Patients With Adult Spinal Deformity: A Retrospective Case Series

STUDY DESIGN

A retrospective case series.

OBJECTIVE

This study aimed to investigate the effects of lateral lumbar interbody fusion (LLIF)-induced unintended tissue damage, including cage subsidence, cage malposition, and hematoma in the psoas major muscle, on the development of thigh symptoms.

SUMMARY OF BACKGROUND DATA

Thigh symptoms are the most frequent complications after LLIF and are assumed to be caused by lumbar plexus compression and/or direct injury to the psoas major muscle. However, the causes and risk factors of thigh symptoms are yet to be fully understood.

MATERIALS AND METHODS

Adult patients with spinal deformity who underwent two-stage surgery using LLIF and a posterior open fusion for the first and second stages, respectively, were included. Computed tomography and magnetic resonance imaging were routinely performed after LLIF before posterior surgery to investigate cage subsidence, cage malposition, and hematoma in the psoas muscle. We evaluated the development of thigh symptoms after LLIF and examined the effects of tissue injury on the occurrence of thigh symptoms. The differences in demographics and surgical and tissue damage parameters were compared between the groups with and without thigh symptoms using unpaired t tests and chi-squared tests. Factors associated with the development of thigh symptoms and muscle weakness were also assessed using logistic regression analysis.

RESULTS

Overall, 130 patients [17 men and 113 women; mean age, 68.7 (range, 47-84)] were included. Thigh symptoms were observed in 52 (40.0%) patients, including muscle weakness and contralateral side symptoms in 20 (15.4%) and 9 (17.3%) patients, respectively. The factors significantly associated with thigh symptoms identified after multiple logistic regression analysis included hematoma (odds ratio: 2.27, 95% CI, 1.03-5.01) and approach from the right side (odds ratio: 2.64, 95% CI, 1.21-5.75). The presence of cage malposition was the only significant factor associated with muscle weakness (odds ratio: 4.12, 95% CI, 1.37-12.4).

CONCLUSIONS

We found unintended tissue injury during LLIF was associated with thigh symptoms. We found that hematoma in the psoas major muscle and cage malposition were the factors associated with thigh symptoms and muscle weakness, respectively.

Establishing a Standardized Clinical Consensus for Reporting Complications Following Lateral Lumbar Interbody Fusion

Background and Objectives: Mitigating post-operative complications is a key metric of success following interbody fusion. LLIF is associated with a unique complication profile when compared to other approaches, and while numerous studies have attempted to report the incidence of post-operative complications, there is currently no consensus regarding their definitions or reporting structure. The aim of this study was to standardize the classification of complications specific to lateral lumbar interbody fusion (LLIF). Materials and Methods: A search algorithm was employed to identify all the articles that described complications following LLIF. A modified Delphi technique was then used to perform three rounds of consensus among twenty-six anonymized experts across seven countries. Published complications were classified as major, minor, or non-complications using a 60% agreement threshold for consensus. Results: A total of 23 articles were extracted, describing 52 individual complications associated with LLIF. In Round 1, forty-one of the fifty-two events were identified as a complication, while seven were considered to be approach-related occurrences. In Round 2, 36 of the 41 events with complication consensus were classified as major or minor. In Round 3, forty-nine of the fifty-two events were ultimately classified into major or minor complications with consensus, while three events remained without agreement. Vascular injuries, long-term neurologic deficits, and return to the operating room for various etiologies were identified as important consensus complications following LLIF. Non-union did not reach significance and was not classified as a complication. Conclusions: These data provide the first, systematic classification scheme of complications following LLIF. These findings may improve the consistency in the future reporting and analysis of surgical outcomes following LLIF.

Segmental artery injury during transforaminal percutaneous endoscopic lumbar discectomy: Two case reports

BACKGROUND

Since Kambin experimentally induced arthroscopy to treat herniated nucleus pulposus, percutaneous endoscopic lumbar discectomy (PELD) has been developed. The branch of the segmental artery around the neural foramen may be damaged during PELD using the transforaminal approach. We report 2 rare cases in which segmental artery injury that occurred during PELD was treated with emergency embolization.

CASE SUMMARY

In case 1, a 31-year-old man was transferred to our emergency department with left lower quadrant abdominal pain after PELD at a local hospital. Lumbar spine magnetic resonance imaging after the surgery showed a hematoma of the left retroperitoneal area and the psoas muscle area. Under suspicion of vascular injury, arteriography was performed. Pseudoaneurysm and blood leakage from the left 4th lumbar segmental artery into the abdominal cavity were identified. Emergency transarterial embolization was performed using fibered microcoils for bleeding of the segmental artery. In case 2, a 75-year-old woman was transferred to our emergency department with low blood pressure, right flank pain, and drowsy mental status after PELD at a local hospital. When the patient arrived at the emergency room, the blood pressure decreased from 107/55 mmHg to 72/47 mmHg. Low blood pressure persisted. Under suspicion of vessel injury, arteriography was performed, and the right 4th lumbar segmental artery rupture was confirmed. Emergency transarterial embolization was performed for bleeding of segmental artery.

CONCLUSION

We were able to find the bleeding focus by angiography and treat the injury of the segmental artery successfully through emergency transarterial embolization.

Challenges Hindering Widespread Adoption of Minimally Invasive Spinal Surgery

Minimally invasive spinal surgery (MISS) techniques offer several beneficial prospects and are being increasingly requested by patients. However, these techniques have not been uniformly adopted by spinal surgeons, and they remain controversial among some. Several barriers have prevented widespread adoption of MISS. These include concerns regarding high start-up costs, limited evidence base, and lack of surgeon training. In addition, the unique approaches involved in MISS expose spinal surgeons to unfamiliar anatomy. Further, while MISS can address a growing spectrum of spinal pathology, some conditions, as well as complications encountered during MISS procedures, require open surgery. This requires surgeons to not only acquire the new and specialized MISS skillset but also maintain their ability to perform open surgery. These factors present challenges common to developing and innovative surgical techniques. Here, we review the barriers preventing wider adoption of MISS and present a framework to promote the safe and effective growth of MISS.

The trajectory characteristics and clinical significance of the left-sided lumbar segmental artery: a prospective cross-sectional radio-anatomical study

Background

Vascular injury to the lumbar segmental arteries is a devastating complication in minimally invasive lumbar interbody fusion. Previous studies on the anatomy of the lumbar segmental arteries are limited. This prospective cross-sectional study aims to quantitatively describe the brief trajectory of the lumbar segmental arteries on the left side (SegAL) and to discuss its clinical significance.

Methods

One hundred and two asymptomatic volunteers were prospectively enrolled and underwent computed tomography angiography (CTA). Anatomical parameters including the existence rate, relative positions and directions of SegAL were measured. Mann-Whitney U tests were performed, and statistical significance was set at P<0.05.

Results

A total of 404 lumbar SegAL were identified. The SegAL of L1, L2 and L3 were identified in all subjects while the L4 SegAL were absent in 9 of 102 (8.8%) and the L5 SegAL were absent in 97 of 102 (95.1%) volunteers. In 25 of 97 (25.8%) volunteers without the L5 SegAL, the branches of the L4 SegAL ran along the disks. Meanwhile, the branches of L3 intersecting over the intervertebral discs (IVD) were found in 8 of 9 (88.9%) subjects without the L4 SegAL and in 4 of 93 (4.3%) subjects with L4 SegAL. The branch angles between the L1, L2 SegAL and the aorta were significantly acute (P<0.05). The L3 SegAL ran approximately vertically with the aorta while the branch angles of the L4 SegAL were significantly blunt (P<0.05). according to the distances measured, on the anterior vertebral walls, the SegAL of L1 and L2 were significantly closer to the inferior vertebral walls than the SegAL of L3 and L4, while on the posterior vertebral walls, the L3 and L4 SegAL were significantly closer to the inferior walls.

Conclusions

Arterial branches may course over the L3-4 and L4-5 IVD spaces and the branches over the L3-4 disks are more likely to be present when L4 segmental arteries are absent, thus posing potential risks of arterial complications. Because of the SegAL adjacent to the disks, the risk of arterial injury may be higher anteriorly at L1 and L2 and higher posteriorly at L3 and L4.

Symptomatic contralateral osteophyte fracture with migration causing lumbar plexopathy during oblique lumbar interbody fusion: illustrative case

BACKGROUND

While performing lateral lumbar interbody fusion surgery, one of the surgical goals is to release the contralateral side with a Cobb elevator, allowing distraction of the interbody space. Many times, there are large osteophytes on the contralateral side, and the osteophytes can be split open with the Cobb or blunt instrument. It is extremely rare for the actual osteophyte to break off from the vertebral body into the contralateral psoas muscle and lumbar plexus.

OBSERVATIONS

The authors report a case of symptomatic lumbar plexopathy caused by an osteophyte fracture after an oblique lumbar interbody fusion requiring a right-sided anterior approach to excise the bony fragment. They illustrate the case with imaging that the radiologist did not comment on, and they also show a video of the surgical excision of the osteophyte through a right-sided anterior lumbar retroperitoneal approach. The authors also show how the patient had spontaneous right-sided electromyography (EMG) firing before excision of the osteophyte and how the EMG firing resolved after excision.

LESSONS

Although the literature is plentiful with regard to ipsilateral approach–related complications, the authors discuss the literature with regard to contralateral complications after minimally invasive lateral lumbar interbody fusion.

Segmental Arteries and Veins at Higher Lumbar Levels Can Intersect the Adjacent Caudal Intervertebral Disc in the Anterior Part of the Spinal Column: A Cadaveric Analysis

Study Design

A cadaveric study.

Purpose

To investigate the anatomical features of segmental arteries and veins in the anterior part of the spinal column to prevent segmental vessel injury.

Overview of Literature

The lateral transpsoas approach to the lumbar intervertebral discs (IVD) is associated with the risk of segmental vessel injury. Previous studies have described the vascular anatomy on the lateral part of the vertebral body. However, there are no studies that describe the segmental vessels on its anterior aspect. Here, we report the important anatomical features of the segmental arteries and veins that can intersect the anterior part of the IVD. These vessels are considered at risk of vascular injury when placing the anterior retractors during lateral lumbar interbody fusion or cutting the anterior longitudinal ligament during anterior column realignment.

Methods

Five formalin-embalmed human cadavers were used. We assessed the proportion of segmental arteries and veins that intersected the IVD in the L2–L5 range and their course on the anterior part of the spinal column.

Results

The segmental arteries and veins commonly intersect the anterior part of the IVD (artery, 28.1%; vein, 42.1%). Seven of 10 (70%) segmental arteries at L2 intersected the IVD, but only one artery intersected the IVD at L3 and L4. The proportions of segmental veins that intersected the IVD were 60%, 50%, and 16.7% at L2, L3, and L4, respectively.

Conclusions

The segmental arteries and veins frequently intersect the IVD in the anterior part of the spinal column. Therefore, it is necessary to consider these individual anatomical features to prevent vascular damage during lateral lumbar interbody fusion surgery.

Clinical results and complications associated with oblique lumbar interbody fusion technique

Background

Oblique lumbar interbody fusion (OLIF) is a minimally invasive technique performed through the antero-oblique trajectory to address a wide range of lumbar pathologies. However, it can lead to complications. We reviewed the results of OLIF and discussed the effective methods to avoid such complications.

Methods

Seventy-nine consecutive patients who underwent OLIF between May 2016 and July 2019 were retrospectively analyzed. They were divided into three groups: stand-alone, posterior, and lateral fixation, according to whether they were followed up with auxiliary internal fixation as well as the fixation methods. Preoperative and last follow-up visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were used to assess the improvement in the lower back and leg pain as well as neurological conditions. We analyzed intervertebral disc height (DH), segmental lumbar lordotic angle (SLL), lumbar lordotic angle (LL), pelvic tilt (PT), pelvic incidence-lumbar lordosis (PI-LL) mismatch, and the cross-section area (CSA) on axial magnetic resonance imaging (MRI) image in different groups. Complications, including thigh symptoms, cage subsidence, neurological injury, and vascular injury, were also noted.

Results

Seventy-nine patients were followed up postoperatively for 23.2±11.5 (range, 12-48) months. Forty-eight (61%) patients underwent stand-alone surgery (without fixation), 15 (19%) patients underwent supplemental percutaneous pedicle screw fixation (posterior fixation), and 16 (20%) patients underwent lateral vertebral instrumentation (lateral fixation). In all three groups, the VAS score and the ODI score had significantly decreased at the final follow-up compared to pre-operation. The DH, SLL, LL, CSA, PT, and PI-LL mismatch had also improved by final follow-up. The most common approach-related complication was thigh symptoms. Of the 79 patients, ipsilateral transient psoas paresis occurred in 9 (11.4%), ipsilateral transient quadriceps weakness in 2 (2.5%), and groin/thigh numbness and pain in 17 (21.5%). Cage subsidence occurred in 8 (10.1%) patients, including five cases of grade 0, one of grade I, and two of grade II. Three (3.8%) patients in this study had a vascular injury.

Conclusions

OLIF is a minimally invasive and effective technique for dealing with degenerative lumbar diseases. However, it should also be noted that this approach carries risks of complications.

Lateral Lumbar Interbody Fusion: Review of Surgical Technique and Postoperative Multimodality Imaging Findings

The lateral lumbar interbody fusion (LLIF) approach is a minimally invasive surgery that can be used as an alternative to traditional lumbar interbody fusion techniques. LLIF accesses the intervertebral disk through the retroperitoneum and psoas muscle to avoid major vessels and visceral organs. The exposure of retroperitoneal structures during LLIF leads to unique complications compared with other surgical approaches. An understanding of the surgical technique and its associated potential complications is necessary for radiologists who interpret imaging before and after LLIF. Preoperative imaging must carefully assess the location of anatomic structures, including major retroperitoneal vasculature, lumbar nerve roots, lumbosacral plexus, and the genitofemoral nerve, relative to the psoas muscle. Multiple imaging modalities can be used in postoperative assessment including radiographs, CT, CT myelography, and MRI. Of these, CT is the preferred modality, because it can assess a range of complications relating to both the retroperitoneal exposure and the spinal instrumentation, as well as bone integrity and fusion status. This article describes surgical approaches for lumbar interbody fusion, comparing the approaches' indications, contraindications, advantages, and disadvantages; reviews the surgical technique of LLIF and relevant anatomic considerations; and illustrates for interpreting radiologists the normal postoperative findings and potential postsurgical complications of LLIF.

Psoas Hematoma and Late Femoral Nerve Palsy After Extreme Lateral Interbody Fusion and Posterior Spinal Fusion with Instrumentation: A Case Report

Introduction

Psoas hematoma is an uncommon complication following spinal surgeries. It has been reported in both extreme lateral interbody fusion (XLIF) and posterior spinal fusion with instrumentation. Minimally invasive techniques are gaining popularity in recent years due to the appealing advantages of reduced operative time, blood loss, hospital stay, and faster recovery.

Case Presentation

We are presenting a case of a 77-year-old male with chronic low back pain, diagnosed to have multilevel degenerative disc disease with central and foraminal disc protrusion at L2-L3, L3-L4, L4-L5 with secondary spinal stenosis, underwent XLIF at L3-L4, L4-L5 and then 2nd stage with posterior L3-L5 fusion with pedicle screws. On the fourth day post-operatively, the patient had flank pain and dropping hemoglobin with femoral nerve palsy symptoms, a CT scan revealed a large psoas hematoma. Conservative management was decided on; a follow-up CT scan and examination showed complete resolution of the hematoma and femoral nerve recovery.

Discussion

The approach to iliopsoas hematoma post spinal surgeries remains controversial. Iliopsoas hematoma should be suspected in any patients post spinal surgeries even with delayed presentations. The decision to proceed with either surgical intervention or conservative management depends on multiple factors, including patient hemodynamic status, progression of collection and femoral nerve palsy.

Conclusion

The exact cause of iliopsoas hematoma post different spinal surgery approaches remains vague. In our opinion, other causes including pre- and post-operative anticoagulants should be investigated. Rushing to drain iliopsoas hematomas in case of femoral nerve palsy might not be the ideal option. Instead, monitoring patient responses to resuscitation and taking a watch and wait approach for femoral nerve palsy might be the proper approach.

Anatomical Study of the Lumbar Segmental Arteries in Relation to the Oblique Lateral Interbody Fusion Approach

OBJECTIVE

To use computed tomography angiography to evaluate the regional anatomy of the lumbar segmental arteries (LAs) associated with the surgical field in oblique lateral interbody fusion (OLIF).

METHODS

Computed tomography angiography images from 50 patients were reviewed. In the sagittal plane, distances from the LA to the upper and inferior edges of the vertebral body were measured in the anterior quarter of the anterior and median lines of the intervertebral disc (IVD). LAs were classified as types I-IV based on the zone in which they passed through the vertebral body.

RESULTS

The LA branch angles were acute (<90°) at L1-L3 and blunt (>90°) at L4-L5. The average distances from the LA to the upper and inferior edges of the vertebral body in the anterior quarter position revealed that La1.2 > Lb1.2 and Lb3.4.5 > La3.4.5. For the IVD of L1-L2, Lb1 < La2; IVD of L2-L3, Lb2 < La3; IVD of L3-L4, Lb3 > La4; IVD of L4-L5, Lb4 > La5. In zone I, the most frequent LA type was type IV at L1 (n = 41; 85.4%) and L2 (n = 42; 84.0%), type III at L3 (n = 20; 40.0%), and type II at L4 (n = 36; 80.0%) and L5 (n = 5; 83.3%). In zone II, the most frequent LA type was type III at L1 (n = 38; 79.2%), L2 (n = 39; 78.0%), L3 (n = 43; 86.0%), and L4 (n = 28; 62.2%), whereas type II was the most frequent LA type at L5 (n = 5; 83.3%). In zone III, type III was the most frequent LA type at L1-L4. In zone IV, type IV was the most frequent LA type at L3 (n = 44; 88.0%), L4 (n = 42; 93.3%), and L5 (n = 6; 100%).

CONCLUSIONS

The risk of LA injury during OLIF is the least when the cage is placed in zones II and III. Care is required during OLIF in zone IV of L3-L5. The fixation pin should be fixed on the upper edge of the lower vertebral body at L1-L2 and L2-L3, and on the lower edge of the upper vertebral body at L3-L4 and L4-L5.

Femoral Neuropathy: A Rare Presentation of Retroperitoneal Hematoma with Review of Literature

Hematomas in close compartments and in pelvic gutters are always challenging to treat and diagnose. A young female on apixaban for recently diagnosed pulmonary thromboembolism (PE) presented to us for the complaints of right sided lower limb weakness. Neurological examination was positive for the right femoral nerve distribution deficit. Computed tomography (CECT) showed large right sided iliopsoas hematoma. Anticoagulation was stopped and was given blood transfusions with which she improved without need of any surgical evacuation. We hereby aim to enrich the understanding of our readers regarding this topic with a review of our experience and other recent publications in medical literature. It is important for the internists to be aware of varied and atypical presentations of retroperitoneal hematoma (RPH) especially following surgical/orthopaedic procedures or in association with anticoagulants and antiplatelets.

Mini-Open Access for Lateral Lumbar Interbody Fusion: Indications, Technique, and Outcomes

Background

Lateral lumbar interbody fusion (LLIF) is a relatively new procedure. It was established as a minimally invasive alternative to traditional open interbody fusion. LLIF allows the surgeon to access the disc space via a retroperitoneal transpsoas muscle approach. Theoretical advantages of the LLIF technique include preservation of the longitudinal ligaments, augmentation of disc height with indirect decompression of neural elements, and insertion of large footprint cages spanning the dense apophyseal ring bilaterally^1,2. The original 2-incision LLIF technique described by Ozgur et al., in 2006, had some inherent limitations³. First, it substantially limited direct visualization of the surgical field and may have endangered nerve and vascular structures. Additionally, it often required multiple separated incisions for multilevel pathologies. Finally, for surgeons with experience in traditional open retroperitoneal surgery, utilization of their previously acquired skills may have been difficult with this approach. To overcome these limitations, we adopted the mini-open lateral approach, which allows for visualization, palpation, and electrophysiologic neurologic confirmation during the procedure⁴.

Description

As detailed below, the patient is positioned in the lateral decubitus position and a single incision is carried out centered between the target discs. For single-level LLIF, the incision spans approximately 3 cm and can be lengthened in small increments for multilevel procedures. After blunt dissection, the retroperitoneal space is entered. The psoas muscle is split under direct visualization, carefully avoiding the traversing nerves with neurosurveillance⁵. A self-retaining retractor is used, and after thorough discectomy, the disc space is sized with trial components. The implant is filled with bone graft materials and is introduced using intraoperative fluoroscopy.

Alternatives

The 2-incision LLIF technique or traditional anterior or posterior lumbar spine interbody fusion techniques might be used instead.

Rationale

LLIF offers the reported advantages of minimally invasive surgery, such as reduced tissue trauma during the approach, low blood loss, shorter length of stay, decreased recovery time, and less postoperative pain. LLIF allows for the placement of a relatively larger interbody cage spanning the dense apophyseal ring bilaterally. The lateral approach preserves the anterior longitudinal ligament and posterior longitudinal ligament. These structures allow for powerful ligamentotaxis and provide extra stability for the construct. Compared with other approaches, LLIF has a reduced risk of visceral and vascular injuries, incidental dural tears, and perioperative infections. Although associated with approach-related complications such as motor and sensory deficits, LLIF can be a safe and versatile procedure^1,2.

Anatomical Evaluation of Lumbar Arteries for Lateral Lumbar Interbody Fusion with Magnetic Resonance Imaging

Introduction

Lateral lumbar interbody fusion (LLIF) is becoming a more common surgical treatment option for adult degenerative lumbar conditions. LLIF is a mini-open access technique with wound retractors, and postoperative hematoma due to segmental vessels injury is reported. Thus, it is considered that there is a need to conduct detailed preoperative examinations to identify where the lumbar vessels are. As far as we know, there are only a few studies investigating the location of the lumbar arteries. This study evaluates the anatomical position of lumbar arteries using magnetic resonance imaging (MRI).

Methods

We studied 101 MRIs of patients with lumbar disease. The length from the upper and lower end plates of the vertebra to the lumbar arteries was measured. The measurement was conducted with coronal MRI images of every quarter slice of L1 to L4 vertebrae. We also investigated sagittal MRI images to determine whether the lumbar vessels are located on intervertebral disc in each level from L1/2 to L5/S1.

Results

The lumbar vessels are not always located at the center of the vertebrae. Some lumbar vessels are located within 8 mm from the end plates. Especially in L4, the lumbar vessels tended to go down from the anterior cranial side to the posterior caudal side (P < 0.01). 8, 24, and 54 lumbar vessels are located at the anterior quarter, the center, and the posterior quarter slice of the vertebrae, respectively, in L4. There were seven lumbar vessels in total located on the vertebral disc level.

Conclusions

It is necessary to investigate where the lumbar arteries are located to prevent its injury in LLIF, because the lumbar artery is not always located at the center of a vertebra. MRIs may provide a valuable information to avoid vascular injury during LLIF.

Lateral and Oblique Lumbar Interbody Fusion-Current Concepts and a Review of Recent Literature

PURPOSE

To review the relevant recent literature regarding minimally invasive, lateral, and oblique approaches to the anterior lumbar spine, with a particular focus on the operative and postoperative complications.

METHODS

A literature search was performed on Pubmed and Web of Science using combinations of the following keywords and their acronyms: lateral lumbar interbody fusion (LLIF), oblique lateral interbody fusion (OLIF), anterior-to-psoas approach (ATP), direct lateral interbody fusion (DLIF), extreme lateral interbody fusion (XLIF), and minimally invasive surgery (MIS). All results from January 2016 through January 2019 were evaluated and all studies evaluating complications and/or outcomes were included in the review.

RECENT FINDINGS

Transient neurological deficit, particularly sensorimotor symptoms of the ipsilateral thigh, remains the most common complication seen in LLIF. Best available current literature demonstrates that approximately 30-40% of patients have postoperative deficits, primarily of the proximal leg. Permanent symptoms are less common, affecting 4-5% of cases. Newer techniques to reduce this rate include different retractors, direct visualization of the nerves, and intraoperative neuromonitoring. OLIF may have lower deficit rates, but the available literature is limited. Subsidence rates in both LLIF and OLIF are comparable to ALIF (anterior lumbar interbody fusion), but further study is required. Supplemental posterior fixation is an active area of investigation that shows favorable biomechanical results, but additional clinical studies are needed. Minimally invasive lumbar interbody fusion techniques continue to advance rapidly. As these techniques continue to mature, evidence-based risk-stratification systems are required to better guide both the patient and clinician in the joint decision-making process for the optimal surgical approach.

Intercostal artery hemorrhage with hemothorax following combined lateral and posterior lumbar interbody fusion: a case report

Introduction

Lateral lumbar interbody fusion (LLIF) is a safe treatment for degenerative spine conditions. However, risk of complications such as vascular injuries remains. We report a unique case of an intercostal artery (ICA) hemorrhage with hemothorax following LLIF.

Case presentation

One hour after a right-sided LLIF L3-4 with posterior decompression L2-4 and L3-5 instrumentation, the patient became hypotensive, anemic and required vasopressor support. Evaluation revealed a right-sided hemothorax, which was caused by a bleeding intercostal artery, laterally at the 10th intercostal space. A lateral thoracotomy was performed to stop the bleeding. After vessel ligation and placement of two chest tubes, the patients' hemodynamics improved. The patient remained intubated overnight and was extubated on the first postoperative day.

Discussion

Vascular injury is a rare complication of LLIF procedures. Most vascular injuries are segmental vessel lacerations, which resolve postoperatively. This is the first case description of ICA bleeding associated with LLIF surgery. Spontaneous ICA bleeding exists, but surgeons should be aware of careful handling in patients with vascular risk factors, especially with regard to patient positioning required in certain spinal surgical approaches. Timely vascular injury identification is critical for hemostasis and clinical management.

Lateral Lumbar Interbody Fusion Revisited: Complication Avoidance and Outcomes with the Mini-Open Approach

OBJECTIVE

To discuss lessons learned from an initial lateral lumbar interbody fusion (LLIF) experience with a focus on evolving surgical technique, complication avoidance, and new motor and sensory outcomes after implementation of a modified surgical approach.

METHODS

A retrospective analysis of a prospectively collected series of all patients undergoing LLIF by the senior author (A.D.L.) from January 2010 to January 2018 after implementation of a modified surgical mini-open technique, compared with previously reported institutional results with the originally recommended percutaneous technique. LLIF-specific complications examined included groin/thigh sensory dysfunction, flank bulge/pseudohernia, psoas-pattern weakness, and femoral nerve injury.

RESULTS

The incidence (19%, n = 98 patients) of groin/thigh sensory dysfunction in our cohort was significantly lower than that of the historical control (60%, n = 59) (P < 0.0001). The incidence of abdominal flank bulge/pseudohernia (2.0%, n = 98 patients) in our cohort was improved but not significantly lower than that of the historical control (4.2%, n = 118) (P = 0.36). The incidence of psoas-pattern weakness (3.1%, n = 98) in our cohort was significantly lower than that of the historical control (23.7%, n = 59) (P = 0.0001). The incidence of femoral nerve injury (0%, n = 98 patients) in our cohort was improved but was not significantly lower than that of the historical control (1.7%, n = 118) (P = 0.20).

CONCLUSIONS

The adoption of an exclusive mini-open muscle-splitting approach with first-look inspection of the lumbosacral plexus nerve elements may improve motor and sensory outcomes in general and the incidence of postoperative groin/thigh sensory dysfunction and psoas-pattern weakness in particular.

Delayed Fatal Lumbar Artery Bleeding Following Less Invasive Posterolateral Decompression and Fusion

STUDY DESIGN

A case report.

OBJECTIVE

The aim of this study was to outline the potential risks of late bleeding from the segmental vessels following less invasively dorsolateral approaches to the thoracolumbar spine.

SUMMARY OF BACKGROUND DATA

A low risk of major intraoperative bleeding, associated traditional dorsolateral approach to the lumbar spine is reported, but segmental arteries and great vessels may be rarely damaged. Spine surgeons who are involved with these approaches should be aware of this rare but potential dangerous vascular complication because it could be life-threatening, particularly in elderly patients with increased morbidity, and/or metastatic disease to the spine.

METHODS

A 76-year-old white woman with a comminuted osteoporotic fracture of the L1-vertebrae with spinal canal encroachment underwent a corpectomy and a 360° fusion with the use of a titanium mesh cage, through a less invasively dorsolateral approach.

RESULTS

Despite the lack of visible intraoperative bleeding and uneventful postoperative period, the patient died on the seventh postoperative day as a result of massive bleeding from a segmental artery at the level of L3 vertebrae body, two levels below our intervention area.

CONCLUSION

This article describes a rare complication of delayed and fatal bleeding of the segmental L3 left vertebral artery following less invasively L1 corpectomy, mesh cage insertion, and pedicle screw fixation in a elderly female patient with history of two malignancies. Although injury to large vessels must always be prevented during these procedures, an injury to the segmental vessels occurs more frequently. The dorsolateral approach and other retroperitoneal approaches to the thoracolumbar region are established methods for the surgical stabilization of comminuted vertebral body fractures, especially on the hands of experienced spine surgeons. Great care should be given postoperatively for signs of bleeding and hematoma and the surgeon should be aware for these life-threatening complications.

LEVEL OF EVIDENCE

5.

Does the Access Angle Change the Risk of Approach-Related Complications in Minimally Invasive Lateral Lumbar Interbody Fusion? An MRI Study

OBJECTIVE

To investigate the potential risk of approach-related complications at different access angles in minimally invasive lateral lumbar interbody fusion.

METHODS

Eighty-six axial magnetic resonance images were obtained to analyze the risk of approach-related complications. The access corridor were simulated at different access angles and the potential risk of neurovascular structure injury was evaluated when the access corridor touching or overlapping the corresponding structures at each angle. Furthermore, the safe corridor length was measured when the corridor width was 18 and 22 mm.

RESULTS

When access angle was 0°, the potential risk of ipsilateral nerve roots injury was 54.7% at L4-L5. When access angle was 45°, the potential risk of abdominal aorta, contralateral nerve roots or central canal injury at L4-L5 was 79.1%, 74.4%, and 30.2%, respectively. The length of the 18mm-wide access corridor was largest at 0° and it could reach 44.5 mm at L3-L4 and 46.4 mm at L4-L5. While the length of the 22 mm-wide access corridor was 42.3 mm at L3-L4 and 44.1 mm at L4-L5 at 0°.

CONCLUSION

Changes in the access angle would not only affect the ipsilateral neurovascular structures, but also might adversely influence the contralateral neural elements. It should be also noted to surgeons that alteration of the access angle changed the corridor length.

Limitations and complications of minimally invasive spinal surgery in adult deformity

Minimally invasive spine (MIS) surgery has rapidly progressed from simple short segment fusions to large adult deformity corrections, with radiographic and clinical outcomes as good as those of open surgery. Anterior longitudinal ligament release (ALLR) and anterior column realignment (ACR) have been key advancements in the ability to correct deformity using MIS techniques. However, patient selection and appropriate preoperative workup is critical to obtain good outcomes and for complication avoidance. Despite favorable outcomes in spinal deformity surgery, MIS techniques are limited in (I) pronounced cervical or thoracic deformity; (II) patients with prior fusion mass; and (III) severe sagittal imbalance necessitating Schwab 5 osteotomy or higher. Guidelines for proper patient selection are needed to guide MIS spine surgeons in choosing the right candidate.

Understanding Retroperitoneal Anatomy for Lateral Approach Spine Surgery

Lateral approach spine surgery provides effective interbody stabilization, and correction and indirect neural decompression with minimal-incision and less invasive surgery compared with conventional open anterior lumbar fusion. It may also avoid the trauma to paraspinal muscles or facet joints found with transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. However, because lateral approach surgery is fundamentally retroperitoneal approach surgery, it carries potential risk to intra- and retroperitoneal structures, as seen in a conventional open anterior approach. There is an innovative lateral approach technique that reveals different anatomical views; however, it requires reconsideration of the traditional surgical anatomy in more detail than a traditional open anterior approach. The retroperitoneum is the compartmentalized space bounded anteriorly by the posterior parietal peritoneum and posteriorly by the transversalis fascia. The retroperitoneum is divided into three compartments by fascial planes: anterior and posterior pararenal spaces and the perirenal space. Lateral approach surgery requires mobilization of the peritoneum and its content and accurate exposure to the posterior pararenal space. The posterior pararenal space is confined anteriorly by the posterior renal fascia, anteromedially by the lateroconal fascia, and posteriorly by the transversalis fascia. The posterior renal fascia, the lateroconal fascia or the peritoneum should be detached from the transversalis fascia and the psoas fascia to allow exposure to the posterior pararenal space. The posterior pararenal space, however, does not allow a clear view and identification of these fasciae as this relationship is variable and the medial extent of the posterior pararenal space varies among patients. Correct anatomical recognition of the retroperitoneum is essential to success in lateral approach surgery. Spine surgeons must be aware that the retroperitoneal membrane and fascia is multilayered and more complex than is commonly understood. Preoperative abdominal images would facilitate more efficient surgical considerations of retroperitoneal membrane and fascia in lateral approach surgery.

Lateral Lumbar Interbody Fusion-Outcomes and Complications

PURPOSE OF REVIEW

Lateral lumbar interbody fusion (LLIF) is a relatively new, minimally invasive technique for interbody fusion. The goal of this review is to provide a general overview of LLIF with a special focus on outcomes and complications.

RECENT FINDINGS

Since the first description of the technique in 2006, the indications for LLIF have expanded and the rate of LLIF procedures performed in the USA has increased. LLIF has several theoretical advantages compared to other approaches including the preservation of the anterior and posterior annular/ligamentous structures, insertion of wide cages resting on the dense apophyseal ring bilaterally, and augmentation of disc height with indirect decompression of neural elements. Favorable long-term outcomes and a reduced risk of visceral/vascular injuries, incidental dural tears, and perioperative infections have been reported. However, approach-related complications such as motor and sensory deficits remain a concern. In well-indicated patients, LLIF can be a safe procedure used for a variety of indications.